(a) Field
The subject matter disclosed generally relates to the field of fax and voice over IP. More specifically, the present disclosure relates to real-time fax over IP communications.
(b) Related Prior Art
Session Initiation Protocol (SIP) is used to control multimedia communications over Internet Protocol (IP) networks.
The market for consumer SIP devices is always expanding. For example, SIP is currently being used in voice over IP, fax communications, video surveillance etc.
At the same time, the concerns about the security of SIP communications over the public Internet are also increasing. The Secure SIP (sSIP) protocol when used with Secure Real Time Protocol (sRTP) can be used to secure audio communications and in turn fax when treated as audio. Proper fax communication however requires use of the T.38 protocol, which treats fax as digital data instead of audio. FIG. 1 illustrates a conventional architecture of real-time Fax Over IP communications using SIP for signaling and User Datagram Protocol Transport Layer (UDPTL) for transporting the T.38 fax media. Unlike sRTP, there does not exist a method/system for securing UDPTL. At the same time T.38 Fax Devices do not support SRTP for transporting the T.38 fax media and therefore can not secure fax communications over IP.
As a result, SIP-based, T.38 Fax communications are transferred over a packet network (such as the Internet) without any security as to authenticity, integrity and confidentiality of the Fax communications being transferred.
Therefore, there is a need in the market for a system and method for securing SIP/UDPTL based T.38 Fax over IP communications.